Earlier News

Earlier Blog News

Ready for another great video on Quantitative Structure Modeling (QSM)? Here’s a YouTube link for an updated version of Markku Åkerblom’s animation demonstrating how QSM works to capture and measure tree structures. You’ll wish you had a tripod for your lidar like his!

TLSIIG at SilviLaser 2015

A great time was had by all at SilviLaser 2015 in La Grande Motte, France, an activity of ISPRS GeoSpatial Week, 28 September – 2 October. A beach resort with unique architecture of the 1960–1975 era, the venue provided ocean views, bathing in the Mediterranean (cold!), and marvelous marine cuisine. As the barrier beach for the adjacent Camargue wetland region, famed for its natural bird habitat of brine ponds and reed-covered marshes, the venue provided lots of opportunity to see nature at work.

The three-day SilviLaser meeting, 28–30 September, featured four sessions with TLS papers, including a dozen by TLSIIG members (abstracts here). TLSIIG members also gathered for an open meeting and gained a number of new members now added to the tlsiig-list. A 1.5-day meeting of the TLSRCN, held October 1–2 at an adjacent venue, brought activities reports by 15 groups and individuals, as well as reports and discussions of six interest groups within the 25 or so RCN participants.

TLS RCN Web Site Now Open

“Coordinating the Development of Terrestrial Lidar Scanning for Aboveground Biomass and Ecological Applications” is the title of a new Research Coordination Network grant from the US National Science Foundation awarded to Boston University, with Alan Strahler as the project leader and 15 institutions participating. Primary goals are to (1) chart the pathway for a low-cost TLS instrument to provide fast and consistent aboveground biomass estimates in forests; and (2) provide new ecological applications of TLS using both commercial and research scanners. Funded for 5 years, the grant will cover the costs of 2–3 meetings and workshops per year.

TLSIIG members recently attended the RSPSOC Annual Meeting at the University of Southampton, September 8-11, and presented four papers. In addition, a meeting of the attending TLSIIG members and interested remote sensors was also held, hosted by Mark Danson and Crystal Schaaf. A post on the SALCA Diaries blogspot provides more information.

EXCEL Workshop, July 21-22, 2015

Planning a trip to the historic Northeast this summer? Swing by the EXCEL Lidar Workshop, July 21 and 22, at the UMass Lowell, sponsored by the University of Massachusetts Experimental Center for Environmental Lidar (EXCEL). Join a diverse group of users, builders, and research funders for two days of lidar fun, including new science and networking in environmental lidar applications. The agenda is now available.

Recent Publications

Can TLS actually distinguish between tree species? Apparently so, if you have the right classification features based on TSL structural measurements. Yi Lin and Martin Herold show how in their new paper in Agricultural and Forest Meterology.

Road trip! Attaching a SICK lidar and an active optical sensor to their 4-wheel drive SUV, Michael Schaefer and Dave Lamb recently cruised through a tall fescue pasture, mapping biomass from height and NDVI. You can read how they did it in their recent article in Remote Sensing.

Who knew? A five-parameter model for calibrating the Dual Waveform Echidna Lidar? That’s what it took to cover the range from 1 m and beyond, thanks to telescopic effects that decrease the signal from midrange (10-12 m) toward the instrument and Lambert’s Law, which decreases the signal from midrange to far range. See the fit in a new Sensors article by Zhan Li et al.

Tired of trying to make sense of those intensities that come with the hits in the point cloud? Maybe you should try some calibration. Lucy Schofield’s new paper in Remote Sensing Letters on the calibration of the SALCA bispectral TLS shows how to turn those messy DNs into apparent reflectances, which are much neater. Just use a neural net!

Who knew? A five-parameter model for calibrating the Dual Waveform Echidna Lidar? That’s what it took to cover the range from 1 m and beyond, thanks to telescopic effects that decrease the signal from midrange (10-12 m) toward the instrument and Lambert’s Law, which decreases the signal from midrange to far range. See the fit in a new Sensors article by Zhan Li et al.

Tired of trying to make sense of those intensities that come with the hits in the point cloud? Maybe you should try some calibration. Lucy Schofield’s new paper in Remote Sensing Letters on the calibration of the SALCA bispectral TLS shows how to turn those messy DNs into apparent reflectances, which are much neater. Just use a neural net!

Trying to get leaf area index from gap probability? And worried about the effect of those pesky branch surfaces, oriented differently from the leaf surfaces? Will Woodgate’s latest paper in Forest Ecology and Management, written with TLSIIGers Mat Disney, John Armston and others, shows how to separately model the leaf angle distribution function and the branch surface distribution function for more accurate results. But you’re still good at the magic zenith angle (57.5°)! Watch out for clumping though….

Is TLS useful for plot-scale forest structure measurements? Or is it a disruptive technology requiring the rethinking of vegetation surveys and their applications? It’s both, according to a new paper in Current Forestry Reports by Glenn Newnham, John Armston, Kim Calders and other TLSIIGers.

Steve Hancock leads a group of authors of a new paper in Remote Sensing of Environment on pulse modeling that shows you the best model to fit the pulses in full waveform data and provide the best estimate of return pulse intensity. Luckily, it’s one of the simplest.

A new paper in Remote Sensing, first-authored by Markku Akerblom of Tampere Tech, tests the use of different geometric shapes in modeling trees from TLS point clouds. The cylinder is simple and robust!